thermal: armada: remove useless register accesses

Prepare the migration to use regmaps by first simplifying the
initialization functions: avoid unnecessary write/read cycles on
configuration registers.
Signed-off-by: NMiquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>

drivers/thermal/armada_thermal.c

@@ -103,16 +103,13 @@ static void armadaxp_init_sensor(struct platform_device *pdev,
 
 	reg = readl_relaxed(priv->control1);
 	reg |= PMU_TDC0_OTF_CAL_MASK;
-	writel(reg, priv->control1);
 
 	/* Reference calibration value */
 	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
 	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
-	writel(reg, priv->control1);
 
 	/* Reset the sensor */
-	reg = readl_relaxed(priv->control1);
-	writel((reg | PMU_TDC0_SW_RST_MASK), priv->control1);
+	reg |= PMU_TDC0_SW_RST_MASK;
 
 	writel(reg, priv->control1);
 
@@ -129,14 +126,13 @@ static void armada370_init_sensor(struct platform_device *pdev,
 
 	reg = readl_relaxed(priv->control1);
 	reg |= PMU_TDC0_OTF_CAL_MASK;
-	writel(reg, priv->control1);
 
 	/* Reference calibration value */
 	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
 	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
-	writel(reg, priv->control1);
 
 	reg &= ~PMU_TDC0_START_CAL_MASK;
+
 	writel(reg, priv->control1);
 
 	msleep(10);